SPINA (Structure Parameter Inference Approach) is a method for calculating constant structure parameters of endocrine feedback control systems from serum or plasma hormone levels obtained in vivo.
A first implementation that has been applied to the in-vivo evaluation of thyroid function allows for calculating the thyroid's maximum secretory capacity (GT) and the sum activity of peripheral 5'-deiodinases (GD) from the levels of TSH, (F)T4 and (F)T3 that have been determined only once (SPINA Thyr). This method is increasingly used in experimental research and clinical trials.
Additional applications targeting other endocrine feedback loops are currently being developed or prepared, respectively.
